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      <a id="fold"></a>
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        <h2>
          <span class="refentrytitle">fold</span>
        </h2>
        <p>fold — 
      Adds artificial foldover to an audio signal.
          </p>
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      <div class="refsect1">
        <a id="idp110382048"></a>
        <h2>Description</h2>
        <p>
      Adds artificial foldover to an audio signal.
    </p>
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      <div class="refsect1">
        <a id="idp110383392"></a>
        <h2>Syntax</h2>
        <pre class="synopsis">ares <span class="command"><strong>fold</strong></span> asig, kincr</pre>
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      <div class="refsect1">
        <a id="idp110385520"></a>
        <h2>Performance</h2>
        <p>
      <span class="emphasis"><em>asig</em></span> -- input signal
    </p>
        <p>
      <span class="emphasis"><em>kincr</em></span> -- amount of foldover expressed in multiple of sampling rate. Must be &gt;= 1
    </p>
        <p>
      <span class="emphasis"><em>fold</em></span> is an opcode which creates artificial foldover.  For example, when <span class="emphasis"><em>kincr</em></span> is equal to 1 with sr=44100, no foldover is added. When <span class="emphasis"><em>kincr</em></span> is set to 2, the foldover is equivalent to a downsampling to 22050, when it is set to 4, to 11025 etc. Fractional values of <span class="emphasis"><em>kincr</em></span> are possible, allowing a continuous variation of foldover amount. This can be used for a wide range of special effects.
    </p>
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      <div class="refsect1">
        <a id="idp110390784"></a>
        <h2>Examples</h2>
        <p>
      Here is an example of the fold opcode. It uses the file <a class="ulink" href="examples/fold.csd" target="_top"><em class="citetitle">fold.csd</em></a>.

      </p>
        <div class="example">
          <a id="idp110392640"></a>
          <p class="title">
            <strong>Example 311. Example of the fold opcode.</strong>
          </p>
          <div class="example-contents">
            <p>See the sections <a class="link" href="UsingRealTime.html" title="Real-Time Audio"><em class="citetitle">Real-time Audio</em></a> and <a class="link" href="CommandFlags.html" title="Csound command line"><em class="citetitle">Command Line Flags</em></a> for more information on using command line flags.</p>
            <pre class="programlisting">
<span class="csdtag">&lt;CsoundSynthesizer&gt;</span>
<span class="csdtag">&lt;CsOptions&gt;</span>
<span class="comment">; Select audio/midi flags here according to platform</span>
-odac      <span class="comment">;;;realtime audio out</span>
<span class="comment">;-iadc    ;;;uncomment -iadc if realtime audio input is needed too</span>
<span class="comment">; For Non-realtime ouput leave only the line below:</span>
<span class="comment">; -o fold.wav -W ;;; for file output any platform</span>
<span class="csdtag">&lt;/CsOptions&gt;</span>
<span class="csdtag">&lt;CsInstruments&gt;</span>

<span class="ohdr">sr</span> <span class="op">=</span> 44100
<span class="ohdr">ksmps</span> <span class="op">=</span> 32
<span class="ohdr">nchnls</span> <span class="op">=</span> 2
<span class="ohdr">0dbfs</span>  <span class="op">=</span> 1

<span class="oblock">instr</span> 1

asig  <span class="opc">poscil3</span> .8, 400, 1 <span class="comment">;very clean sine</span>
kincr <span class="opc">line</span> p4, p3, p5
asig  <span class="opc">fold</span> asig, kincr
      <span class="opc">outs</span> asig, asig

<span class="oblock">endin</span>
<span class="csdtag">&lt;/CsInstruments&gt;</span>
<span class="csdtag">&lt;CsScore&gt;</span>
<span class="comment">;sine wave.</span>
<span class="stamnt">f</span> 1 0 16384 10 1

<span class="stamnt">i</span> 1 0  4 2  2 
<span class="stamnt">i</span> 1 5  4 5  5 
<span class="stamnt">i</span> 1 10 4 10 10 
<span class="stamnt">i</span> 1 15 4 1 100	<span class="comment">; Vary the fold-over amount from 1 to 100</span>

<span class="stamnt">e</span>
<span class="csdtag">&lt;/CsScore&gt;</span>
<span class="csdtag">&lt;/CsoundSynthesizer&gt;</span>
</pre>
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        <p><br class="example-break" />
    </p>
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      <div class="refsect1">
        <a id="idp110396960"></a>
        <h2>Credits</h2>
        <p>
      </p>
        <table border="0" summary="Simple list" class="simplelist">
          <tr>
            <td>Author: Gabriel Maldonado</td>
          </tr>
          <tr>
            <td>Italy</td>
          </tr>
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            <td>1999</td>
          </tr>
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        <p>
    </p>
        <p>New in Csound version 3.56</p>
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